Pumping of rubber latex and the like and apparatus therefor



Sept 2@ 11932. H. WILLSHAW ET AL PUMPING OF RUBBER LATEX AND THELIKE'AND APPARATUS THEREFOR Filed Feb. 28, 1928 2 SheetS-Sheec l Sept.20, E932. H. wlLLsHAw ET AL 'mg@ PUMPING OF RUBBER LATEX AND THE LIKEAND APPARATUS THEREFOR Filed Feb. 28, 1928 2 Sheets-Sheet 2 3 /5mul-Inghamy 15 Patented Sept. 20,l 1932Y UNITED .STATES PATENT OFFICEBIARRY WILLSHAW, WALTER GEORGE GGR-HAM AND yROGrllR FREDERICK LEE, OF

BIRMINGHAM, ENGLAND, ASSIGNORS T AMERICAN ANODE, NEW YORK, N. Y., ACORIYYORATION OF DELAWARE INCORPORATED, 0F

PUMIPING- 0F RUBBER LATEX AND THE LIKE AND APPARATUS THEREFORApplication led February 28, 1928, Serial No. 2573691, and in GreatBritain March 2, 1927.

This invention relates to means for effecting the forced movement orpumping of liquid dispersions or emulsions` which are liable to undergoflocculation or coagulation on being subjected to, for instanceimmoderate agitation or impact shock.

Liquid dispersions or emulsions contemplated as coming underconsideration in this invention comprise the latices of rubber or wother vegetable resins, artificial dispersions such as of rubber or ofother vegetable resins or of coagulated rubber or of waste rubberl orrubber reclaim or vulcanized dispersions of rubber or other vegetableresins, or artitieial dispersions of synthetic resins or cellulosecompounds or again mixtures of any p of the aforesaid dispersions, anylof which may or may not contain any one or more of the vusual and knowncompounding ingredients.

2o According to the present invention the means utilized for effectingthe forced movement or pumping of liquid dispersions of the aforesaidkinds and nature is a pump adapted to function by the deformation orreformation or similar displacement of a resilient member or chamber, itbeing preferable that the reformation of said member or chamber drawsthe dispersion from one vessel and that the deformation of the saidmember or chamber discharges the dispersion so drawn into another vesselor vice versa. In this manner the clogging of any interstices withcoagulum from the dispersions is avoided.

The invention is applicable in a variety of instances necessitating theforced movement or pumping or circulation of dispersions, particularlylatex. Thus it is especially suitable for use in the circulation ofliquid dispersions through a container, such` as is described in ourapplication of even date, while it can equally well be utilized in thepumping of latex from transport tankers into storage vats in thefactory.

Referring to latex, almost insuperable dif- `ficulties attend the use ofpumps having slid- `ing parts, or bearings or glands, which contact withthe latex. l It its practically impossible to prevent the infiltrationof the rubber globules between the stationary and the moving parts andconsequent rapid coagulation of the latex adjacent those parts.

Thus the use of pumps of the usual reciproeating piston type isprecluded in as'much as if the coagulum formed adjacent the piston isallowed to remain, the pump rapidly becomes clogged and unable tofunction. To avoid the difliculties associated with this kind of pump,various other expedient-s have been resorted to. For instance rotary orturbine umps have been utilized, but these as applied to the pumping oflatex have been comparatively complicated and ineicient. Bearings orglands exposed to the latex rapidly become' clogged with coagulum andspecial constructions .have had to be devised in which the rotors arecarried on bearings wholly clear of the latex. Air ypumps have also beenutilized for the movement of latex but known kinds of such pumps haveonly a very limited range of application and are not generallypracticable.

The invention will now be described by Way.

l of example with reference to the accompanying drawings in which Figure1 is a' sectional side elevation of a pump constructed for use withrubber latex. Figure 2 is a plan view thereof, while Figures?) and 4show diagrammatically alternative arrangements.

Referring to Figures 1 and 2, the resilient member is in the form of adisc diaphragm l extending across anoriflce 2 in a chamber or cavity 3disposed between the inlet and outlet valves 4 and 5 respectively.

The said member is preferably actuated by a reciprocating rod 6 theoperating mechanism for which ,includes a driven pulley 7, gearing 8, acrank shaft 9, a connecting rod 10, and a bell crank lever 11 fulcrumedat I0 12. That surface of the diaphragm 1 which contacts with the latexis removed from the surrounding surfaces. It has been found that yif thediaphragm is allowed to contact or to approach closely the walls of thecavity 3i ifar as is convenient from the surrounding a suitably arrangedstop surfaces. Further in ball valves means are provided to preventundue displacement of the ball thereof-both to ensure that the ballreturns accurately to its seating and that it so returns almostimmediately after cessation of discharge. As shown in-thedrawings, saidmeans conveniently consistsv of 14 limiting the vertical lift of thesaid ball.

In the alternative construction shown diagrammatically in Figure 3, thecavity 3 between the valves 4 and 5 is Wholly ineXtensible and theresilient member is in the form of an envelope l5 distensiblebyinflation. To allow said envelope to collapse into a small compass, thesame is preferably formed to assume deflated-the cross sectional shapeindicated at 16. The actuating fluid is alternately admitted andexhausted via a suitable valve 17-distention of the envelope causingdisdisplacement, through the outlet valve 5, of the latex around it inthe cavity, and contraction of the said envelope drawing more lateX intothe said cavity through the inlet valve 4.

In general, however, it will be apparent that the resilient member maytake any convenient form. Thus for example the said resilient member maybe in the form of a bellows-like chamber preferably disposed between twosubstantially rigid end members adlapted to move towards and away fromeach ot er.

In a further modification designed specifl fined to valves such as ballvalves adapted to be actuated by the displacement of the latex, it willbe apparent that alternatively we may utilize positively actuatedvalves. For instance as illustrated diagrammatically in Figure 4 suchvalves may comprise distensible members 18 and 19 adapted to close theorilices into the chamber 3 of the inlet and outlet pipes 4a and 5arespectively. The inflation to close the inlet pipe. As shown in Figure4 x the diaphragm may be fluid actuated under the control of adistributing valve 21.l Finally it will be apparent that the featuresdescribed in connection with one application of our invention may whereapplicable, with or without modification or addition, be utilized inconnection with any of the other applications of the said invention.

What we claim is l. Means for pumping aqueous dispersions which arecoagulated by friction, comprising a pump body, a resilient diaphragmconstituting one wall of the pump body, means engaging` the diaphragmfor repeatedly changing the internal volume of the pump body, and inletand outlet valves comprising valve'chambers, inflatable members withinthe valve chambers adapted to obstruct the fluid passage when inliatcdand leave a passage for the fluid when deflated, and means forsuccessively infiating and deflating the said members in timedrelationship with the (halnges in the internal volume of the pump 2. Apump valve comprising a valve chamber, an inflatable member adapted toobstruct the fluid passage when inflated andleave a passage for thefluid when deflated, and means for periodically inflating and deflatingthe said member.' p

3. A pump valve comprisinga valve chamber, an inflatable sac adapted tofill the valve chamber when inflated and leave a passage for the fluidwhen deflated, and means for periodically iniiating and deflating thesac.

' 4. A pump comprising a chamber, fluid operated means for periodicallydrawing the fluid to be pumped into the chamber and forcing it out ofthe chamber, inlet and outlet valves comprising valve chambers,inflatable members within the valve chambers adapted to obstruct vthefluid passage when inflated and leave a passage for the fluid whendeflated, and conduits connecting the inflatable members with the fluidactuating the pump proper whereby the valves areopened and closed insynchronism with the operation of the pump proper. y

5. A pump comprising a pump body, a resilient diaphragm constituting onewall of the pump body, a hydraulic cylinder operatively connected to thediaphragm, means for introducing a liquid under pressure alternatelyinto the two ends of the cylinder to reciprocate the said diaphragm,inlet and outlet valves comprising valve chambers, inflatable memberswithin the valve chambers adapted to obstruct the Huid passage wheninated and leave a passage for the uid when deflated, and conduitsconnectin the respective inflatable members with the uid in the two endsof the cylinder whereby the valves are opened and closed in synchronismwith the movements of the diaphragm.-

In witness whereof, we have hereunto signed our names.

HARRY WILLSHAW. 1 WALTER GEORGE GORHAM. ROGER FREDERICK LEE.

